Toyota Tacoma (2015-2018) Service Manual: Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
The 4 wheel drive control ECU records DTCs when the ECU detects a malfunction in the ECU itself or in system circuits.
The DTCs can be read through the DLC3 of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform troubleshooting.
2. CHECK DLC3
(a) Inspect the battery voltage.
Standard voltage:
11 to 14 V
If the voltage is below 11 V, recharge the battery before proceeding.
(b) Check the DLC3 (See page .gif)
).
3. FUNCTION OF INDICATOR LIGHT
(a) When a problem occurs in the touch select 2-4 and high-low system, a message is displayed on the multi-information display and/or the 4LO indicator light on the combination meter assembly rapidly blinks* to inform the driver of the problem.
- *: 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
(b) Indicator light status (illumination and blinking) or multi-information display status when DTC is output.
TOUCH SELECT 2-4 AND HIGH-LOW SYSTEM|
DTC No. |
4WD Indicator Light (Green) |
4LO Indicator Light |
Multi-information Display Message |
|---|---|---|---|
|
U0100 |
When 2WD: Not illuminated When H4 or L4: Illuminated |
Rapidly blinking |
- |
|
U0122 |
Not illuminated |
Rapidly blinking*1 |
2WD-4WD mode change malfunction visit your dealer |
|
U0416 |
|||
|
P163B |
|||
|
P17A0 |
|||
|
P17A4 |
Not illuminated |
Not illuminated |
2WD-4WD mode change malfunction visit your dealer |
|
P17A8 |
Not illuminated |
Rapidly blinking |
2WD-4WD mode change malfunction visit your dealer |
|
P17A9 |
|||
|
P17AA |
|||
|
P17AC |
|||
|
P17C7 |
Not illuminated |
When 2WD or H4: Not illuminated When L4: Illuminated |
2WD-4WD mode change malfunction visit your dealer |
|
P17C8 |
|||
|
P2772 |
When 2WD: Not illuminated When H4 or L4: Illuminated |
Rapidly blinking |
- |
|
P279E |
Not illuminated |
Rapidly blinking |
2WD-4WD mode change malfunction visit your dealer |
Rapidly blinking: Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
- *1: P163B may also display the 2WD/4WD mode status.
System Diagram
SYSTEM DIAGRAM
Transmitting ECU (Transmitter)
Receiving ECU
Signal
Communication Method
4 wheel drive control ECU
Skid ...
Dtc Check / Clear
DTC CHECK / CLEAR
1. CHECK DTC
(a) Check the DTCs.
(1) Turn the ignition switch off.
(2) Connect the Techstream to the DLC3.
(3) Turn the ignition switch to ON.
(4) Turn the Techstream on.
(5) ...
Other materials:
Inspection
INSPECTION
PROCEDURE
1. INSPECT BRAKE VACUUM CHECK VALVE ASSEMBLY
(a) Check that there is ventilation from the booster to the engine, and
no ventilation from the engine to the booster.
If the results are not as specified, replace the vacuum check valve.
...
CD Sound Skips
PROCEDURE
1.
CHECK CD
(a) Check that the CD is not deformed or cracked.
OK:
No deformation or cracks on the CD
NG
CD IS FAULTY
OK
...
Freeze Frame Data
FREEZE FRAME DATA
DESCRIPTION
(a) When a pre-collision system DTC is stored, the millimeter wave radar sensor
assembly stores the current vehicle (ECU or sensor) state as Freeze Frame Data.
CHECK FREEZE FRAME DATA
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c ...
